It compiles OK with no errors!
Trying to create a model based on this grammar it gives error,extraneous input 'integer' [or 'string'] expecting RULE_ID, when using any of the DefaultDataType, string, integer, ... as an attribute type!

entity Person {
id: integer
name: string
}

How to solve this problem?
How to export a set of default data types from the grammar to the instances?